Prenatal Diagnosis and Care Flashcards
Gestational Age
Days-weeks from LMP
Embryo
What we call the spermegg from time of fertilization to 8wks (GA 10wks)
Fetus
What we call the spermegg after 8 wks until time of birth
Infant
Time between delivery and 1yr old
First trimester
1-14wks GA
Second Trimester
14-28wks GA
Third Trimester
28wks until delivery
Previable
Infant delivered before 24wks
Preterm
Infant delivered 24-37 wks
Term
37-42 wks
Post Term
> 42 wks (yikes)
Parity
Number of pregnancies that led to a birth after 20 weeks
What counts in parity? (if it’s after 20 weeks)
Term
preterm
Abortions
Living children
When is an S3 gallop physiologic
Pregnancy! It’s due to the inc BV. The output, stroke and pulse will also jump up bc of this extra blood
BP changes in pregnancy
In the second trimester we’ll take a dip in BP, it’ll come back to normal in the third trimester.
This is due to changes in peripheral vascular resistance
Where does the bladder go during pregnancy?
Down and in! It becomes an intra-abdominal organ during pregnancy.
Kidney function changes in pregnancy
GFR will increase by 50% dt the extra blood
BUN and serum Cr will decrease by 25%
Marked inc in renin and angiotensin, but a reduced vascular sensitivity to their hypertensive effects
Hematologic changes in pregnancy
Plasma volume inc by 50%
RBC volume inc by 30%
*WBC count increases- think about the proinflammatory response that goes along with pregnancy
Platelet count dec but is still WNL
Cervix changes in pregnancy
Inc cervical muscous secretions
Inc water content and vascularity
Where do we expect the fundus to be @ 20 wks
Tip of the umbilicus
What does it mean when the baby “drops”
It means the baby’s head is engaging with the pelvis
Serum or urine HCG? When will we see a positive result?
Uguale! Serum and urine are just as sensitive.
They can be positive 1 week after fertilization, which is one week before you miss your period.
How to determine if it’s a viable pregnancy
US and HCG
5 weeks: TvUS can show a gestational sac or HCG of 1,500-2,000
6 weeks: TvUS can show afetal heart or an HCG of 5,000-6,000
Two questions you should ask every patient before you do anything else
1) Was this pregnancy planned
2) Are you planning to continue this pregnancy?
1 leading cause of pregnancy leading death. What are the RF for it
DV- Homicide.
RF are age <20, AA, late or no prenatal care
Pregnancy signs
Chadwick's sign Hegar's sign Goodell's sign Ladin's sign Breast swelling/tenderness Linea nigra Telangiectasias Palmar erythema
Chadwick’s sign
Bluish discoloration of the vagina and cervix
Hegar’s sign
Softening of the uterine consistency and ability to palpate or compress the connection between the cervix and the fundus
Goodell’s sign
Softening and cyanosis of the cervix after week 4
Ladin’s sign
Softening of the uterus after week 6
Symptoms of pregnancy (different than signs)
Amenorrhea
N/V
Breast pain
Quickening (fetal movement)
Initial PE for a pregnancy woman
Vitals Thyroid heart Lungs Breast Abdomen Pelvic (Pap, GC, bimanual) Extremities-edema** Influenza vax
Nagele’s Rule
For calculating the EDD
LMP - 3 months + 7 days
How to calculate the EDD when LMP is unknown
US!
Most accurate in first trimester. Done by measuring CML, can predict is with an error of 3-5 days
Labs in the first trimester
CBC Type and Screen RPR/VDRL -> syph Rubella Ab screen HBV antigen VZV titer G/C cx PPD Pap UA and U Cx HIV testing
CBC in pregnancy
When is it done? What do we expect the WBC to look like? RBC? MCV? Thrombocytopenia?
Done with initial labs and at 28 weeks Slightly elevated WBC Dilutional anemia normal MCV low? Consider thalassemia Slight thrombocytopenia is normal
When to transfuse iron dt dilutional anemia in pregnancy
When HCT <32%
When do we get worried about HELLP w/ thrombocytopenia
When Plt <100
Type and Screen in regards to Rh/rhogam
All Rh - moms get rhogam at 28 weeks
Rh - moms with a + baby will get rhogam PP
When to do a test of cure for G/C in a pregnant woman
4 weeks after tx. We want to make sure this doesn’t get passed onto the baby
Non Trep Syph testing (it’s the weird acronym)
VDRL/RPR
Trep Syph testing (acronyms again)
FTA-ABS
RF for a false positive for VDRL/RPR , and what to do when you get a false pos
Being pregnant is a risk factor! If this is positive, do the (more expensive) trep syph testing and get a FTA-ABS
Risks of untxed syphilis for baby
Miscarriage, stillbirth, neonatal death or baby with severe neurological problems. 50% of untxed syph winds up passing to the baby
Guide to screening for cystic fibrosis/when to be worried
If mom is a carrier, screen dad.
If dad is not a carrier, we’re not worried.
If mom and dad is a carrier, be worried
What is MS-AFP
Maternal Serum AFP level. High levels can be a marker for neural tube defects, but it’s far from perfect. 5% false pos rate and only 85% proper detection rate
What defines AMA and what kind of screening do we offer these patients
> 35 yo.
Offer maternal serum screening and genetic counseling with diagnostic tests (chorionic sampling or amnio)
Modes of maternal serum screening
MS-AFP
Quad screen
Sequential screening
NIPT testing (non invasive prenatal testing- blood test for downs etc)
Are the screening tests diagnostic? If they’re positive, what are the next steps?
No! They’re just for screening. If they’re positive we’ll do actual diagnostic screening (LvL 2 US, amnio, chorionic)
Second trimester diagnostics (everybody gets these)
What weeks do people get these?
MSAFP (16-18wks)
Quad screen
US (18-20wks)
What can an ultrasound show you at 18-20wks
A lot of soft markers for bad stuff.
We’ll do a fetal survey, get an amniotic fluid volume, placental location and gestational age
What does a quad screen test for?
Can it be used if multiple gestation?
Tests for Trisomy 21, Trisomy 18 and open NTD
Cannot be used for multiple gestations.
Not diagnostic, send for L2 US and amnio if positive
What makes up sequential screening?
1) Blood tests for serum PAPP-A and HCG @ 11-13wks
2) US for nuchal translucency @ 11-13wks
3) More blood tests for MS-AFP, estriol, HCG, inhibin @ 15-18wks*** This second round of blood tests is much more sensitive than the first round.
False positive rate of sequential screening
1%. It’s really good
US Soft markers for aneuploidy
Ventricular septal defect
Choroid plexus cyst
Thickened nuchal fold
Is cffDNA diagnostic? What’s the next step after this
It’s considered diagnostic, but we’d still do amnio after a positive.
What is cffDNA analysis? What does it check for?
Cell-free Fetal DNA analysis. Tests for fetal trisomies using mom’s blood. Checks for trisomy 21, 18 and 13.
Recommendations for testing cffDNA
1) AMA
2) US soft markers for aneuploidy
3) Hx of pregnancy w/ trisomy
4) Positive test result for trisomy from quad/sequential screen
When do we do an US in pregnancy
1) Initial visit to measure CRL if uncertain LMP
2) First trimester bleeding
3) Anatomic survey @ 20 weeks
4) any time fundal height >3cm discrepancy from GA
5) Confirm presentation at/after 37 weeks
What is amniocentesis
Sticking a needle in the sac while under US guidance to tell us some more about what’s going on with the kiddo
When is amniocentesis done & why
Amnio is traditionally done at 15-20weeks to get a fetal karyotype. Should not be done <15 weeks because there’s a much higher risk of pregnancy loss.
What determines the rate of procedure-related fetal loss
Provider experience
Complications of amnio
Transient vaginal spotting Amniotic fluid leakage Preterm labor Chorioamnionitis Needle injury to fetus
What is chorionic Villus Sampling?
It’s when you place a cath into the intrauterine cavity and aspirate a small amount of chorionic villi from the placenta. Can get you a fetal karyotype 5 weeks before an amnio
Complications of Chorionic villus sampling?
Preterm labor
PROM
Previable delivery
Fetal injury
What has a higher risk of procedure-related fetal loss, amnio or chorioinic villus sampling?
It’s the same as long as your in the hands of an experienced provider
What is cordocentesis?
PUBS! Puncture the umbilical vein under US guidance and get a direct blood sample. Gets us a fetal karyotype. Rarely done for diagnostics, but can be used to further evaluate chromosomal mosaichism as a last resort
Procedure-related pregnancy loss of cordo
<2%
Third trimester standard diagnostics. (blood tests)
When is it done?
Done at 27-29 weeks.
CBC- check for dilutional anemia GLT (glucose loading test) RPR/VDRL CXR if PPD + GBS strep cx at 36wks
High risk? Consider repeat G/C/HIV
Two methods of testing for GDM (gestationaln diabetes mellitus)
1) Glucose loading test -> screening tool. If positive, do GTT
2) Glucose Tolerance Test -> Diagnostic tool
Glucose loading test (GLT)
Give 50g PO glucose as a loading dose and check serum glu 1hr later
Glucose Tolerance Test (GTT)
And what’s considered a positive result?
Get a fasting serum glucose. Then give 100g PO glucose loading dose. Do serial serum glucoses at 1,2 and 3 hrs after PO glu.
If >2 of these values are elevated it’s a diagnosis for GDM
Positive values for elevated glucose levels in a GTT
Fasting >95
1hr >180
2hr >155
3hr >140
What to get at routine prenatal visits
BP Weight Urine dip for protein/glu Fundal height, estimated weight & position Auscultation of fetal heart tones
When to screen for GBS
How to screen for GBS
What do we use to tx GBS
What if they’re allergic
1) 36 wks
2) Vagina/anus swab
3) PCN
4) Vanco. Make sure they’re actually allergic
How often do we see these pregnant women
a) When they’re <28wks (before 3rd trimester)
b) When they’re 28-36 wks (third trimester to term)
c) >36 wks (term)
a) <28 weeks? Once a month
b) 28-36 wks? Twice a month
c) Term? Once a week
Questions for a pregnant woman in the first trimester
Cramping?
Bleeding?- spotting is normal
N/V?
Q’s for a pregnant woman in the second trimester
Cramping?
Bleeding?- spotting is definitely not normal
Fetal movement?
Q’s for a pregnant woman in the third trimester
Contractions?
Any bleeding?- we might see a tiny bit of spotting in the third trimester since the cervix is SO vascular. But we should still bring these women in.
Leaking of fluid?
Baby still moving?
Routine Problems in Preg (the ones she actually said out loud)
PICA- get a nutrition consult
Round ligament pain (esp common if 1st pregnancy)
Urinary freq (can also be a UTI, get a dip)
Carpal tunnel syndrome (will clear up ~6wks PP)
How much folic acid do our ladies need
800mcg, most effective when given 2 months prior and during 1st month. Better to get it from dietary sources
What vitamins should our ladies avoid
Fat soluble ones! DAKE
Limiting caffeine in pregnancy
<500mg a day
When to consider a nutrition referral in a pregnant patient
Not enough weight gain
PICA
Eating disorder
Prenatal nutrition, how much __ should a pregnant woman be getting per day
a) Calories
b) Protein
c) iron
d) calcium
a) 2,200
b) 75g total
c) 30-60 mg
d) 1200 mg
How much weight do we expect you to gain in pregnancy?
How much if you’re obese (BMI>30)
How much if you’re underweight (BMI<20)
Avg is 25-35 lbs. Every organ volume will inc in weight. Like just the extra blood is 4lb
Obese? 15lb
Underweight? 40lb
How much do we want to limit radiation exposure in pregnant women
5 episodes max
Some safe “go to” meds for pregnant ladies
Prenatal Vitamins Tylenol Benadryl Sudafed (if no HTN) Tums FeSO4 Colace
For UTI, we can use ___ all the way until the third trimester. Third trimester we use ___
Bactrim until third trimester, after that it’s macrobid. Or just macrobid throughout
When do we talk about PP contraception
Third trimester
Goals of antepartum fetal surveillance
Prevent fetal death
Forms of antepartum fetal surveillance
Fetal movement assessment NST Contraction stress test Fetal biophysical profile Amniotic fluid index
Fetal movement assessment:
Indication?
Technique?
Indication: Mom perceives dec fetal movement
Technique: Mom counts number of kicks in a specific amount of time. Have mom eat/drink and then sit or lie down
Non Stress test
1) What is it?
2) What’s considered a reactive result?
3) What’s considered a nonreactive result?
1) Measure of fetal HR w/ movement. The HR of a healthy infant will temporarily accelerate when the kid moves
2) Reactive (normal) = >2 fetal HR accelerations within 20 min
3) Non reactive: Insufficient HR accel within 40 min
Contraction Stress test-
What are we looking for?
We’re looking for the presence/absence of late fetal HR decel in response to uterine contractions
What is a late decel?
Decel that hit nadir after then peak of the contraction, and drag on a little bit after the end of the contraction. This aren’t good
What is a variable decel?
Decels for no reason. Cord compression, can be a lot of things. Not as big of a worry
What makes up a biophysical profile (like a fetus well being check). How is it scored?
NST, fetal breathing movements, fetal movement, fetal tone, amniotic fluid index.
Scored from 0-10. Normal is 8-10, equivocal is 6, bad is <4
Regardless of the composite score, if ____ is present we want further evaluation
Oligohydraminos
Oligohydraminos
No US measured pocket of fluid that’s >2cm. Or we have an overall amniotic fluid index <5cm. This is always bad, there is not enough fluid for the baby and it’s a sign that the placenta has his it’s expiration date
Polyhydraminos
When AFI >24cm. It’s when there’s excess fluid. This can be totally normal, or it can cause PROM and malpresentatino
When do we start antepartum surveillance?
Between 32-34 weeks for most pregnancies. Start at 31 weeks if there’s a hx of an unexplained FD. Or if there’s some kind of ACOG indications
When should a vag delivery PP patient follow up in clinic?
6 weeks later. Address lochia, voiding, BM, bfing, PPD, contraception. If having stress incontinence 6 weeks PP consider pelvic floor PT
When should a section PP pt FU?
2 and 6 weeks. Do an incision check
When should we see a PP pt w/ gestational HTN back in clinic?
4 days. Preeclampsia can last 6 weeks post delivery. Plus, the cure for preeclampsia is delivery. So you want to make sure that the crazy high BP meds they needed pre-delivery are still necessary now, so you don’t bottom out their pressure since they don’t have preeclampsia anymore. Makes sense?
